Follicular fluid redox balance and DNA damage according to PCOS phenotype

Classification of polycystic ovary syndrome (PCOS) according to their phenotypes is important in terms of understanding which parameter has clinical and laboratory implications. This study was designed to measure the follicular fluid total oxidant capacity (TOC) and total antioxidant capacity (TAC) and DNA degradation products of 8-hydroxy-2'-deoxyguanosine (8-OHdG) levels in patients with different PCOS phenotypes undergoing In-Vitro Fertilization/Intra-Cytoplasmic Sperm Injection (IVF/ICSI).

Thirty women who were diagnosed with PCOS and twenty infertile patients who did not have the clinical and laboratory findings of PCOS were included. Women carrying at least two of the three parameters below were considered to have PCOS. (1) Biochemical or clinical manifestations of hyperandrogenism (HA); (2) Ovulatory dysfunction (OD); (3) Polycystic ovarian morphology (PCOM). Patients were then classified into four different PCOS phenotypes: (1) Phenotype A is also known as classical PCOS and meets all three criteria (HA/OD/PCOM). (2) Phenotype B has two criteria, HA and OD. (3) Phenotype C consists of HA and PCOM criteria. (4) Phenotype D is the non-hyperandrogenic form and consists of OD and PCOM criteria. Antagonist protocol was used in both PCOS and control groups. During oocyte pick-up, follicular fluid of the dominant follicle was collected. TAC and TOC levels, which are redox balance markers, and 8-OHdG levels, which are DNA degradation products, were measured in follicular fluid samples (FF).

Follicular fluid 8-OHdG levels of all four types of phenotypes were significantly higher than the control group. When the phenotype groups were evaluated among themselves, FF-8-OHdG levels of each group were found to be similar. Serum TOC levels of each phenotype group were found to be significantly higher than the control group. TAC levels of the patients in the control group were significantly higher than the other four phenotype groups. Oxidative stress index (OSI) values were significantly higher in all four phenotype groups compared to the control group. OSI values of phenotype B and D groups were significantly higher than phenotypes A and C.

In each phenotype of PCOS, TOC and OSI increased while TAC decreased. Increased OSI leads to DNA degradation and an increase in the level of 8-OHdG. The cumulative effect of oxidative stress and DNA degradation may be the main mechanism of PCOS-related subfertility.